The Cosmotron

Early in the Laboratory's history, the consortium of universities
responsible for founding the new research center, decided that
Brookhaven should provide unique facilities for high energy physics
research. In April 1948, the Atomic Energy Commission approved a
plan for a proton synchrotron to be built at Brookhaven. The new
machine would accelerate protons to previously unheard of energies,
comparable to those of cosmic rays showering the earth's outer
atmosphere. It would be called the Cosmotron.

The Cosmotron, 1949

There were accelerators before the Cosmotron, but this machine
was the first accelerator in the world to send particles to energies
in the billion electron volt, or GeV, region. The Cosmotron reached
its full design energy of 3.3 GeV in January 1953.

Not only was the Cosmotron the world's highest energy
accelerator, it was also the first synchrotron to provide an
external beam of particles for experimentation outside the
accelerator itself. Early on, the intensity of the beam extracted
for experiments was ten billion protons per pulse. By 1966,
intensity had been increased nearly 100 times.

The Cosmotron was the first machine to produce all the types of
negative and positive mesons known to exist in cosmic rays, making
possible the discoveries of the K0L meson and the first vector
meson. It was also the first accelerator to produce heavy unstable
particles, some of which were formerly called "V" particles, and
this led directly to the experimental confirmation of the theory of
associated production of strange particles.

After fourteen years of service to the physics research
community, the Cosmotron ceased operation in 1966 and was dismantled
in 1969. Knowledge gained from the Cosmotron would lead to
revolutionary design improvements and pave the way for construction of Brookhaven's next
big accelerator: the Alternating Gradient Synchrotron.